EP0825358B1 - Méthode d'étude de la transmission du bruit dans une structure - Google Patents

Méthode d'étude de la transmission du bruit dans une structure Download PDF

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Publication number
EP0825358B1
EP0825358B1 EP96890134A EP96890134A EP0825358B1 EP 0825358 B1 EP0825358 B1 EP 0825358B1 EP 96890134 A EP96890134 A EP 96890134A EP 96890134 A EP96890134 A EP 96890134A EP 0825358 B1 EP0825358 B1 EP 0825358B1
Authority
EP
European Patent Office
Prior art keywords
controller
sensor
actuating device
parts
vibration
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP96890134A
Other languages
German (de)
English (en)
Other versions
EP0825358A1 (fr
Inventor
David Charles Quinn
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AVL List GmbH
Original Assignee
AVL List GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by AVL List GmbH filed Critical AVL List GmbH
Priority to AT96890134T priority Critical patent/ATE192555T1/de
Priority to EP96890134A priority patent/EP0825358B1/fr
Priority to ES96890134T priority patent/ES2145419T3/es
Publication of EP0825358A1 publication Critical patent/EP0825358A1/fr
Application granted granted Critical
Publication of EP0825358B1 publication Critical patent/EP0825358B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K5/00—Arrangement or mounting of internal-combustion or jet-propulsion units
    • B60K5/12—Arrangement of engine supports
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
    • F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F7/00—Vibration-dampers; Shock-absorbers
    • F16F7/10—Vibration-dampers; Shock-absorbers using inertia effect
    • F16F7/1005—Vibration-dampers; Shock-absorbers using inertia effect characterised by active control of the mass
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H1/00—Measuring characteristics of vibrations in solids by using direct conduction to the detector
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M17/00—Testing of vehicles
    • G01M17/007—Wheeled or endless-tracked vehicles
    • G01M17/04—Suspension or damping

Definitions

  • the invention relates to a method for investigation of structure borne noise paths in a complex structure according the preamble of claim 1. Furthermore the invention is directed to a system for investigation of structure borne noise paths in a complex structure according to the preamble of claim 8.
  • One example of such complex structure is a vehicle body on which a combustion engine is mounted. In this case the combustion engine forms the first part of the structure whereas the vehicle body forms the other part. Engine mounts forming connecting elements between these parts are provided to minimize transfer of vibrations from the combustion engine to the vehicle body.
  • Another example of such complex structure is the suspension of a wheel of a vehicle. Vibrations are induced by the axle of a road wheel of the vehicle into the vehicle body.
  • One method of prior art is to attach one or more sensors like accelerometers on critical parts of the structure to be able to determine the amount and the velocity of deviations of these parts.
  • US-A 5,133,527 and US-A 5,418,858 disclose active mount systems in which vibrations and noise are minimized by an electronic circuit in which data from sensors are inputted and which calculates a certain control force to be generated by some actuators. Such systems can be very effective and allow a substantial reduction of noise and vibration. However, such systems make it necessary that all components have to be built in into each vehicle produced and to work over the whole lifetime of such vehicle. Therefore the costs of such systems are high.
  • US 5,332,061 A describes an active vibration control (AVC) system for attenuating vibrational frequency components generated by an engine and transferred through an engine mounting unit to vibrate a motor vehicle body.
  • AVC active vibration control
  • this method consists of the steps of the characterizing part of claim 1.
  • the behaviour of the structure is changed by the application of the active control so that information of the system is obtainable.
  • the change of behaviour may be conducted without mounting or dismounting parts of the structure. In this way it is possible to calculate forces acting in the structure in different operating conditions even if it is not possible to measure them directly. Further it is possible to simulate different parts and their influence on the behaviour of the structure. So it is possible to simulate another engine mount instead of the mount actually used in the structure. Since these operations are possible by changing the control strategy of the controller such experiments are very effective and easy to conduct.
  • the frequency range of operation for vehicle applications, will typically be 30 HZ to 800 HZ.
  • the system can be used in one of two modes of operation
  • Fig. 1 shows schematically a structure with a system according to the present invention.
  • a vehicle 1 is equipped with an internal combustion engine 2.
  • the combustion engine 2 comprises an engine mount 3 with a resilient element 4 which is attached at the part 5 of the vehicle body which is not shown for sake of convenience.
  • an electromagnetic type actuator 6 which is designed to apply predetermined forces to the part 5 of the vehicle body.
  • a sensor 7 which is an accelerometer senses the dislocation of part 5 in the vicinity of engine mount 3.
  • a further sensor 8 senses the dislocation of the engine mount 3 on the side of the combustion engine 2.
  • a force measuring element 9 measures the force acting on the part 5 of the vehicle body induced by actuator 6.
  • a reference signal sensor 10 detects the speed of the engine of the vehicle.
  • a microphone 11 or number of microphones is (are) disposed in the interior of the vehicle preferably in a position corresponding to the occupants head(s).
  • An additional sensor 12 detects vibrations at another part of the vehicle body.
  • a controller 20 consists internally of an adaptive cancellation controller 21 and a setting and evaluation unit 22.
  • the controller 20 is connected to sensors 7, 8, 9, 10, 12 and to the microphone 11. Based upon signals inputted by these sensors the adaptive cancellation controller calculates a control signal. This control signal is fed to an amplifier 23 which drives the actuator 6.
  • the control signal of the cancellation controller 21 is calculated according to a control strategy determined by the setting and evaluation unit 22.
  • Such control strategy which may be also extended to a multi-channel vibration control is disclosed in Elliott, Stothers and Nelson "a multiple error LMS algorithm and its application to the active control of sound and vibration" IEEE transactions on acoustics, speech and signal processing Oct. 1978. Further details of such control strategies are disclosed in US-A 5,133,527 and US-A 5,418,858. The method is not limited to these control strategies.
  • One example of operation of the system of the present invention is that a control strategy is chosen so that dislocation of sensor 7 is minimized.
  • This simulates a situation in which part 5 of the vehicle body is very stiff at the frequency or frequencies of control.
  • the force measured by sensor 9 which may be a strain gauge corresponds to the force acting in part 5 and in the engine mount 3 if it would be very stiff.
  • By changing the control strategy it is possible to simulate different degrees of stiffness of part 5. In such cases it is not possible to determine the force acting on part 5 based upon the signal of force sensor 9.
  • comparing dislocations measured by sensors 7 and 8 and considering the characteristic of the resilient element 4 it is possible to calculate the force transferred by this engine mount 3. It will be noticed that by this arrangement displacements and forces may be measured and calculated with respect to a predetermined direction. If it is necessary to investigate forces acting in other directions additional sensors and actuators have to be applied.
  • controller microphone 11 and the additional sensor 12 allow to evaluate the results of different simulations in terms of riding comfort.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Transportation (AREA)
  • Combustion & Propulsion (AREA)
  • Acoustics & Sound (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Vibration Prevention Devices (AREA)
  • Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)

Claims (9)

  1. Procédé de recherche de chemins de bruits créés par la structure dans une structure complexe constituée d'au moins deux parties (2, 5) reliées par des éléments de liaison tels que par exemple des amortisseurs ou Silentblocs, des montures de moteur (3) ou des isolateurs de suspension, dans lequel l'une de ces parties (2, 5) génère des vibrations produisant des bruits, ce procédé comprenant les étapes suivantes :
    fixer au moins un dispositif d'actionnement comprenant une masse d'inertie supplémentaire et un actionneur (6), à un point se trouvant au voisinage d'un élément de liaison (4) entre deux parties (2, 5) de la structure, cet actionneur (6) étant relié à un contrôleur (21),
    fixer au moins un détecteur (7) de détection de l'amplitude de vibration au voisinage du point où le dispositif d'actionnement est fixé ou placé dans le dispositif d'actionnement, ce détecteur au moins unique (7) étant relié au contrôleur (20),
    obtenir un signal ou des signaux provenant de la partie (3) qui génère des vibrations,
    relier en entraínement le contrôleur (20) au dispositif d'actionnement (6) pour activer ce dispositif d'actionnement (6),
    caractérisé par les étapes suivantes consistant à :
    fournir plus d'une seule stratégie de commande pour entraíner le contrôleur (20),
    entraíner le contrôleur (20) suivant différentes stratégies de commande prédéterminées compte tenu du signal ou des signaux de référence,
    mesurer le changement de vibration ou de bruit à des endroits prédéterminés de la structure pour les différentes stratégies de commande,
    calculer l'influence de la force de vibration transmise par l'élément de liaison (4), sur les valeurs mesurées.
  2. Procédé selon la revendication 1,
    dans lequel
    le contrôleur (20) effectue une annulation à bande étroite des harmoniques de vibration des signaux de référence.
  3. Procédé selon la revendication 1,
    dans lequel
    le contrôleur (20) effectue une annulation à large bande de la vibration.
  4. Procédé selon la revendication 1 ou 2,
    dans lequel
    le contrôleur (20) utilise une stratégie d'alimentation avant directe.
  5. Procédé selon la revendication 1 ou 2,
    dans lequel
    le contrôleur (20) utilise une stratégie de commande de rétroaction.
  6. Procédé selon l'une quelconque des revendications 1 à 5,
    dans lequel
    le contrôleur (20) est monté pour permettre l'émulation d'absorbeurs dynamiques.
  7. Procédé selon l'une quelconque des revendications 1 à 6,
    dans lequel
    une stratégie de commande consiste à minimiser la désorganisation au point où est fixé l'actionneur (6).
  8. Système de recherche de chemins de bruits créés par la structure dans une structure complexe constituée d'au moins deux parties reliées par des éléments de liaison tels que des amortisseurs ou Silentblocs ou des montures de moteur (3), dans lequel l'une de ces parties (2, 5) génère des vibrations produisant des bruits, ce système comprenant :
    un dispositif d'actionnement (6) fixé à un point situé au voisinage de l'élément de liaison,
    un détecteur (7) de détection des vibrations, ce détecteur étant fixé à un point de la structure situé au voisinage du dispositif d'actionnement,
    un détecteur de signal de référence (10) pour obtenir un signal de référence provenant de la partie qui génère des vibrations,
    au moins un autre dispositif de détection (8, 9, 11, 12) pour évaluer l'amplitude de la vibration ou du bruit transmis par la structure,
    un contrôleur (20) relié à l'actionneur (6), au détecteur (7), au détecteur de signal de référence (10) et à l'autre dispositif de détection au moins unique (8, 9, 11, 12), ce contrôleur (20) étant conçu pour entraíner l'actionneur (6) suivant les signaux reçus du détecteur (7), du détecteur de signal de référence (10) et de l'autre dispositif de détection au moins unique (8, 9, 11, 12),
    caractérisé en ce que
    le contrôleur (20) comprend une annulation et un bloc de réglage et d'évaluation (22) pour établir différentes stratégies de commande et pour obtenir une information relative au comportement dynamique de la structure.
  9. Système selon la revendication 8,
    dans lequel
    l'autre dispositif de détection au moins unique est un microphone (11), un accéléromètre (12) ou un dispositif de mesure de force (9) ou encore des multiples de ces dispositifs de détection.
EP96890134A 1996-08-21 1996-08-21 Méthode d'étude de la transmission du bruit dans une structure Expired - Lifetime EP0825358B1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
AT96890134T ATE192555T1 (de) 1996-08-21 1996-08-21 Verfahren zum untersuchen von körperschallwegen
EP96890134A EP0825358B1 (fr) 1996-08-21 1996-08-21 Méthode d'étude de la transmission du bruit dans une structure
ES96890134T ES2145419T3 (es) 1996-08-21 1996-08-21 Metodo para la investigacion de recorridos de ruido soportados en estructuras.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP96890134A EP0825358B1 (fr) 1996-08-21 1996-08-21 Méthode d'étude de la transmission du bruit dans une structure

Publications (2)

Publication Number Publication Date
EP0825358A1 EP0825358A1 (fr) 1998-02-25
EP0825358B1 true EP0825358B1 (fr) 2000-05-03

Family

ID=8226206

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96890134A Expired - Lifetime EP0825358B1 (fr) 1996-08-21 1996-08-21 Méthode d'étude de la transmission du bruit dans une structure

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EP (1) EP0825358B1 (fr)
AT (1) ATE192555T1 (fr)
ES (1) ES2145419T3 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008025730A1 (de) * 2008-05-29 2009-12-03 Dr. Ing. H.C. F. Porsche Aktiengesellschaft Verfahren zur Simulation von Schwingungsprüfungen

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2113755B1 (fr) 2008-05-01 2012-02-01 LMS International NV Analyse de chemin de transfert vibratoire et/ou acoustique
EP3769982B1 (fr) * 2019-07-26 2023-11-01 Dn Automotive Italy S.R.L. Méthode de génération de force pour une réduction de vibration active pour un support supérieur d'amortisseur ou pour un support de suspension moteur et véhicules
IT201900025024A1 (it) * 2019-12-20 2021-06-20 Dtr Vms Italy S R L Metodo di generazione di una forzante per la riduzione attiva di vibrazioni per un attacco superiore ammortizzatore o per un attacco sospensione motore con compensazione rumore abitacolo
DE102021113291B4 (de) * 2021-05-21 2023-06-29 Universität Rostock, Körperschaft des öffentlichen Rechts Verfahren und Vorrichtung zur Ermittlung wenigstens einer auf ein Antriebsaggregat wirkenden Kraft und/oder wenigstens eines auf ein Antriebsaggregat wirkenden Antriebsdrehmomentes

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1020851A (en) * 1963-01-11 1966-02-23 Rover Co Ltd Suspension of machinery and other bodies
US5133527A (en) * 1989-08-10 1992-07-28 Mechanical Technology Incorporated Active mounts
US5332061A (en) * 1993-03-12 1994-07-26 General Motors Corporation Active vibration control system for attenuating engine generated vibrations in a vehicle
US5418858A (en) * 1994-07-11 1995-05-23 Cooper Tire & Rubber Company Method and apparatus for intelligent active and semi-active vibration control

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008025730A1 (de) * 2008-05-29 2009-12-03 Dr. Ing. H.C. F. Porsche Aktiengesellschaft Verfahren zur Simulation von Schwingungsprüfungen

Also Published As

Publication number Publication date
ATE192555T1 (de) 2000-05-15
ES2145419T3 (es) 2000-07-01
EP0825358A1 (fr) 1998-02-25

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